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Ideal Weight Calculator

Estimate your ideal body weight using several commonly referenced height-based formulas. Compare Devine, Robinson, Miller and Hamwi estimates, see their average, and view a broader healthy BMI-based weight range for your height.

Enter Your Details

These formulas provide mathematical reference weights rather than one medically correct or universally ideal body weight.

cm
kg
Average formula estimate
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Enter your height to compare several formulas.
Healthy BMI-based range—
Current weight—
Difference from formula average—
Formulas compared4

Ideal Weight Formula Comparison

These formulas were developed for different purposes and can produce different estimates.

Devine formula—
Robinson formula—
Miller formula—
Hamwi formula—
Average—

Weight Position

This visual compares your current weight with a broad BMI-based range for your height. It is not a diagnosis.

LowerBMI rangeHigher

Ideal Weight by Formula

Compare the main height-based formulas and the assumptions used by each.

FormulaEstimated WeightMain InputNotes
Devine—Height and sexCommonly referenced historical IBW formula
Robinson—Height and sexAlternative height-based estimate
Miller—Height and sexAnother variation of IBW calculation
Hamwi—Height and sexHistorical rule-of-thumb estimate

What Is an Ideal Weight Calculator?

An ideal weight calculator estimates body weight from height using one or more mathematical formulas. The term “ideal weight” can be misleading because there is no single body weight that is medically ideal for every person of the same height.

This calculator therefore compares several formulas rather than presenting one result as the correct answer.

How Does This Ideal Weight Calculator Work?

The calculator uses your height and the sex selection required by the historical formulas. It calculates estimates using the Devine, Robinson, Miller and Hamwi formulas, then calculates the average of those four estimates.

Devine Ideal Weight Formula

Male

50 kg + 2.3 kg for each inch over 5 feet

Female

45.5 kg + 2.3 kg for each inch over 5 feet

Robinson Ideal Weight Formula

Male

52 kg + 1.9 kg for each inch over 5 feet

Female

49 kg + 1.7 kg for each inch over 5 feet

Miller Ideal Weight Formula

Male

56.2 kg + 1.41 kg for each inch over 5 feet

Female

53.1 kg + 1.36 kg for each inch over 5 feet

Hamwi Ideal Weight Formula

Male

48 kg + 2.7 kg for each inch over 5 feet

Female

45.5 kg + 2.2 kg for each inch over 5 feet

What Is a Healthy Weight Range?

A broader weight range can be calculated from height using standard adult BMI cut-offs. This calculator displays the approximate weight corresponding to BMI values of 18.5 to 24.9.

Lower Weight = 18.5 × Height in metres²

Upper Weight = 24.9 × Height in metres²

Ideal Weight vs BMI

Ideal-weight formulas produce a single reference estimate, while BMI can be used to generate a broader weight range for a given height. Neither method directly measures body fat, muscle mass, bone structure, fat distribution or overall health.

For BMI, use the BMI Calculator.

Why Do Ideal Weight Formulas Give Different Answers?

These equations were developed at different times and with different assumptions. Some were originally designed for clinical or medication-related reference purposes rather than to define an aesthetically or medically ideal body weight.

A difference between formulas is expected.

The average result is included only as a convenient comparison and should not be interpreted as a prescribed target weight.

Ideal Weight Calculator Assumptions

  • Uses Devine, Robinson, Miller and Hamwi formulas.
  • Uses height and formula sex selection.
  • Converts metric height to inches internally.
  • Shows an average of the four formula results.
  • Calculates a separate BMI-based weight range from BMI 18.5 to 24.9.
  • Does not directly account for age, body-fat percentage, muscle mass or body frame.
  • Is intended primarily for adult informational use.
  • Does not provide a personalised target weight or medical diagnosis.

Related Health & Fitness Calculators

BMI CalculatorCalculate Body Mass Index and a healthy BMI-based weight range. Body Fat CalculatorEstimate body-fat percentage and lean body mass. BMR CalculatorEstimate basal metabolic rate and resting energy needs. TDEE CalculatorEstimate total daily energy expenditure and maintenance calories. Macro CalculatorEstimate protein, carbohydrate and fat targets. Health & Fitness CalculatorsBrowse all health, fitness and nutrition tools.

Ideal Weight Calculator FAQs

How is ideal body weight calculated?

Different formulas use height and sex-specific constants to produce mathematical reference weights. This calculator compares Devine, Robinson, Miller and Hamwi formulas.

Which ideal weight formula is best?

There is no universally correct ideal-weight formula. Each equation has different assumptions and can produce a different result.

Is ideal weight the same as healthy weight?

Not necessarily. Ideal-weight formulas produce reference values, while healthy weight is broader and depends on more than height alone.

Should I use the calculated average as my target weight?

Not automatically. The average is a mathematical comparison of several formulas and is not a personalised weight recommendation.

Health information: This Ideal Weight Calculator provides mathematical reference estimates from historical height-based formulas. There is no single ideal body weight that applies to every person of the same height. The results do not directly account for body composition, age, muscle mass, body frame, health conditions or other individual factors. They are informational only and should not be treated as a personalised weight target, diagnosis or medical recommendation.